Q. What does Jesus mean when He says "the light of the body is the eye"? Our eyes don't light anything. And what can He mean by "the light that is in thee be darkness"?
A. Jesus does not mean that the eyes physically light up the body. But to understand what He means, let's look at the Scriptures, Matthew 6:22-23 and Luke 11:34-36.
Matthew 6:22-23 says, "The light of the body is the eye: if therefore thine eye be single, thy whole body shall be full of light. But if thine eye be evil, thy whole body shall be full of darkness. If therefore the light that is in thee be darkness, how great is that darkness!" The passage in Luke is very similar: "The light of the body is the eye: therefore when thine eye is single, thy whole body also is full of light; but when thine eye is evil, thy body also is full of darkness. Take heed therefore that the light which is in thee be not darkness. If thy whole body therefore be full of light, having no part dark, the whole shall be full of light, as when the bright shining of a candle doth give thee light" (Luke 11:34-36).
By "light" of the body, Jesus means "lamp," "illuminator," that which sheds light on something [the Greek word is luchnos]. A lamp illuminates where we are going, what we are working on, and so forth. Likewise, the eye shows us where we are going and what we are doing.
The word "single" in this passage is the key to understanding Jesus' point. The Greek word translated "single" is haplous. It literally means without folds. It can be used to mean "not complex," "simple," "single as to purpose." If you were driving at night down a dark road and your headlights suddenly started pointing in different directions—left, right, up, down, straight ahead, right, etc.—you would become confused and might even have an accident. You would say your headlights are bad.
Now imagine your eyes doing the same thing, continually looking right, left, up, down, etc. It would be hard to walk, let alone do your work. Of course, there are times when this does happen, not because of a physical affliction but because we have trouble focusing our attention on one thing. The problem is not very serious when a child walks into a candy shop and doesn't know where to look first. It can become more serious when driving. One accident on the side of the road will often cause drivers passing by to "rubberneck" to see what is going on, take their eyes off the road ahead, and run into the car in front or even go off the road. And I would not want to trust a surgeon whose eyes often stray from his work to see what else is going on in the room.
What Jesus is saying is that we should have singleness of vision or purpose. We should set our eyes on the goal and keep them there. Jesus tried to get us to see this point many times through various instructions and illustrations. In Matthew 6, just before telling us about the light of the body, He told us not to lay up treasures for ourselves on earth but to lay up treasure in heaven. That's singleness of purpose and begins to tell us what the goal is. Then, in verse 24, He tells us that no man can serve two masters, "Ye cannot serve God and mammon [wealth personified]." He then tells us not to take anxious care about the things of this world, which leads to the well-known verse: "But seek ye first the kingdom of God, and his righteousness; and all these things shall be added unto you" (Matthew 6:33). Again, this is to have single vision.
The goal Jesus wants us to set our eyes on is the kingdom of God. What does this mean? In the kingdom parables, Jesus several times makes the point that the kingdom of God is in this world, growing in this world even while evil is being injected into it, mixing with it, and growing with it. Naturally, Jesus does not want us to be seeking the evil of this world. He wants us to be seeking the kingdom or reign or rule of God. Does He mean that we are to be seeking it in the politics and governments of this world? No! Have you noticed that such things are pictured by beasts in Bible prophecy? That's because, while as with all things the governments of this world ultimately serve God's purpose, such things are part of the evil of this world. Where, then, are we to seek the rule of God? We are to seek God's rule in our lives—in our lives and in the lives of others through furthering the Gospel. The Bible never says to seek the kingdom any other way.
Remember, Matthew 6:33 says to "seek ye first the kingdom of God, and his righteousness." We can find God's righteousness only in Jesus Christ. He is the One whom Jeremiah twice calls "the Lord our Righteousness" (Jeremiah 23:6 and 33:16). In Acts 3:14, Jesus Christ is called "the Holy One and the Just." The word "Just" is translated from "dikaion," which could just as correctly have been translated "the Righteous." The same is true of "Just One" in Acts 7:52. We seek the kingdom of God and His righteousness by seeking Jesus Christ as our Savior, wanting Him to reign in our lives, wanting to have His mind in us (Philippians 2:5) through being sanctified by His Word (John 17:17), and wanting others to also share in this through spreading the Gospel. If seeking the kingdom of God and His righteousness is our goal and we don't stray from it, we will be full of light or enlightened.
Notice that Jesus contrasts having our eyes "single" with having our eyes "evil" [ponēros—evil or wicked]. Remember the bad headlights that kept changing what they were shining on. They were no good for their purpose. Jesus considers anything but having the single goal of the kingdom of God to be evil. Allowing ourselves to become distracted from the very purpose for which He called us is wicked. Having double vision—the kingdom of God and something else—is to be full of darkness. This is contrary to what we might naturally think. We might think that it is okay as long as the kingdom of God is one of our goals. The light might be a little dimmed, but it would still be light. But that is not what Jesus says. He says that such a mixed light is really darkness: "If therefore the light that is in thee be darkness, how great is that darkness!" "Light" in this verse is from phōs, which literally means "light," and can metaphorically mean "truth," "knowledge," or "reason." Mixed light, putting other goals beside the goal of the kingdom of God in your life, is really darkness; in fact, it is great darkness or a lack of true knowledge or enlightenment. This is a serious matter.
Why is it wrong to have another goal alongside the kingdom of God? Frankly, I think it is because it is a New Testament form of idolatry. In the Old Covenant God made with Israel, in the Ten Commandments, God told them, "Thou shalt have no other gods before me. Thou shalt not make unto thee any graven image, or any likeness of any thing that is in heaven above, or that is in the earth beneath, or that is in the water under the earth: Thou shalt not bow down thyself to them, nor serve them: for I the LORD thy God am a jealous God, visiting the iniquity of the fathers upon the children unto the third and fourth generation of them that hate me" (Exodus 20:3-5). But Christians should now understand that idolatry includes more than just setting up a graven image. It is to put anything—job, house, the cares of this world, the pleasures of this world, even family—on a par with wanting the righteousness of God and His rule for ourselves and others. This does not mean we should have nothing to do with these other things. But we must keep all in a godly perspective. Spreading God's love in our family and teaching our children the Scriptures is part of putting the kingdom of God first. So is being a good, Christian example on the job. Do all to the glory of God, and keep your eyes always fixed on the goal.
It is so easy to read something like this and then walk away, get distracted, lose our focus, and become entangled again in the affairs of this world. Remember, "No man that warreth entangleth himself with the affairs of this life; that he may please him who hath chosen him to be a soldier" (2 Timothy 2:4). You are "bought with a price: therefore glorify God in your body, and in your spirit, which are God's" (1 Corinthians 6:20).
And everyone who competes
exercises self-control in all things. Now they compete in order that
they may receive a perishable crown, but we compete for an imperishable
1 Corinthians 9:25